The bottom bracket is the dohickey that connects your two crank-arms together, and secures them within the bottom of the bike frame. The bottom bracket has threads around the outside that secure it into the hole in the frame. Inside, bearings surround a rotating spindle -- this lets the pedals turn free from the frame.
This tutorial will demonstrate how to remove and install a sealed cartridge bottom bracket, found on most modern bicycles. A cartridge bottom bracket usually has two main components. The cartridge contains the sealed bearings and spindle, and is usually threaded into the right or drive side of your frame.
The bottom bracket is what allows your cranks to turn. If your cranks are wobbly, or there's a noise coming from between your cranks when you pedal, then you may need to overhaul your bottom bracket. This instructable a remix of FriendofHumanity's 'ble will show how to remove, clean, lube and adjust most adjustable bottom brackets using only common hand tools and one "special" tool.
Your bottom bracket is a part of your bike that is prone to wear. This guide will help you replace your bottom bracket. In this how-to we look at four types of bottom brackets: 1.
The bottom bracket, or 'BB' as it often gets shortened to, is the humble bearing which supports the rotation of the cranks. This out of the way components tucked mostly out of sight between the crank arms has morphed to include nearly a dozen different styles and sizes. Even so, the traditional threaded BSA threaded version remains the most popular, and for good reason, it works and is easy to fit so this guide concentrates on this type.
This article will discuss the removal and installation of the common cartridge bottom brackets of the three-piece cranksets. Most cartridge bottom brackets are held by retaining rings or cups on either side. See Adjustable-Type Bottom Brackets. One type has a fixed flange on the right side drive side.
Bottom bracket service falls into one of two categories: you either change them with a new one or exchange bearings. Other brands do sell replacement bearings or seals to get the job done. Bikes with threadless bottom brackets PF30 or similar require you to punch out your old bearings using a BBT